1. The Field of the Invention.
The present invention relates generally to a folding chair, and/or a stackable/storable folding chair system. More particularly, the present invention relates to a folding chair having a frame with a curved spline profile, and having a seat and legs which fold or collapse into a volume defined by the frame, such that a number of folded chairs may be stacked adjacent one another with the curved spline profiles of the frames nesting or indexing the chairs in a dense, stable relationship.
2. The Background Art
Folding chairs are often used in situations in which it is desirable or necessary to provide varying numbers and/or varying layouts of chairs, such as during conventions, seminars, conferences, etc. In addition, folding chairs are often used in multipurpose areas in which patron seating is required for some functions, but a large open space is required for other functions necessitating storage of the chairs. For example, some organizations have buildings with a multipurpose room which may be used for banquets, seminars, conventions, etc., with chairs set up, or for a dance, sporting event, etc., with the folding chairs removed.
It is desirable that the folding chairs be capable of being folded and stacked for storage so that the chairs take up less room when they are not required. It will be appreciated that some situations or events will require thousands of folding chairs, all of which may need to be folded and stored at any given period. Thus, the chairs must be folded and stored such that they have a high storage density to minimize the storage space required. It will be appreciated that any extra thickness of a chair when folded becomes significant when numerous folding chairs are involved. For example, with a thousand stacked folding chairs, a folding chair which saves one extra inch in the folded position results in over 80 linear feet of saved storage space.
One disadvantage with many prior art folding chairs is the bulk or thickness of the chair in the folded position. Many typical folding chairs still remain several inches thick in the folded position, and thus are less dense when stored. For example, many typical folding chairs have seats which fold adjacent to or abutting the legs, and/or have front and back legs which fold against one another, such that the thickness of the chairs in the folded position comprises the thickness of both the front and rear legs, and/or the thickness of the legs and the seat. Another disadvantage of many conventional folding chairs is that they fold awkwardly, with bulky folded configurations and/or various protruding members.
In addition, it is desirable that the folding chairs be easily storable or stackable, and be stable when stored/stacked. Many typical prior art folding chairs are stored merely by leaning one chair against a wall and subsequent chairs in a series against the first chair. It will be appreciated that a plurality of folding chairs stacked against a wall have a potential domino effect, with all of the chairs subject to being knocked over. Other prior art folding chairs have complicated and expensive hanging rack systems. For example, a wheeled cart might have a plurality of support arms from which a plurality of folding chairs are suspended. One disadvantage of these types of systems is that chairs on the end of the hangers tend to fall off the rack, and the wheeled racks are difficult to move and maneuver.
Some types of prior art folding chairs have back rest portions which protrude from the chair and into an adjacent folding chair. For example, a folding chair may have a back portion which curves outwardly to protrude from the frame of the chair, and into the frame of and adjacent folding chair. Although this relationship allows the chairs to be stored with greater density, the chairs tend to be unstable in a stored position. The broad rounded backs of the chairs act as ramps which, fail to resist movement of an adjacent chair. In addition, the chairs are still relatively thick and bulky.
It also is desirable that the chairs be easy to set up and take down, or fold and unfold. It will be appreciated that there is considerable time involved in setting up and taking down thousands of chairs. One disadvantage of many prior art folding chairs is that they are difficult to both unfold and fold. For example, most folding chairs require the person to use both hands to fold and unfold the chair. One hand usually has to grasp the back of the chair while the other hand has to grab and pivot the seat in or out.
It also is desirable that the chairs be comfortable. Typical prior art folding chairs have rigid metal seats and seat backs which can be hard and uncomfortable. One disadvantage of many prior art folding chairs is that the chairs either fold well and are uncomfortable, or are comfortable but are awkward in folding. Thus, there tends to be a trade off between comfort and foldability. Some chairs provide a cushion. But these chairs still utilize the rigid metal seat bottoms and seat backs, and the cushions tend to make the chairs even thicker when folded.
In addition, it is desirable that the chair provide proper support, or be ergonomically designed. One disadvantage of many prior art chairs is that the angle between the back rest and the seat is dictated by the folding mechanism of the chair. Thus, in an effort to create a folding chair, the proper ergonomic design of the back rest and seat is often compromised in order to obtain a chair that folds more easily.
Another disadvantage of many typical prior art folding chairs is that they have a relatively small back support which may not adequately support a user""s back. The small back support is often a function of the folding configuration of the chair. Again, the back support is often compromised in order to obtain a chair that folds. For example, the seat may be configured to fold upwardly or towards the back support, so that a relatively large space must exist between the back support and the seat so that the seat may fold into that space. That space is usually located where a user requires back support.
It also is desirable that the folding chair be durable. It will be appreciated that the chair will be alternately stored and used, folded and unfolded, innumerable times. Similarly, it is desirable that the folding chair be strong. The chair must be able to support persons of various weight, often in potentially abusive conditions.
It also is desirable that the folding chair be safe. It will be appreciated that as the various parts of the chair fold, there is a potential for fingers and the like to become pinched within the folding mechanisms.
Therefore, it would be advantageous to develop a folding chair capable of folding for high density storage. It also would be advantageous to develop such a folding chair which is more stable and safe in the folded and stored position. It would further be advantageous to develop a folding chair which (i) may be easily folded and unfolded; (ii) is comfortable and safe; and (iii) is durable, strong, and cost effective.
It is therefore an object of the present invention to provide a folding chair which folds relatively thin to maximize storage density.
It is another object of the present invention to provide such a folding chair which stores safely and is stable when stored, and/or stacked.
It is another object of the present invention to provide a folding chair which is easily folded and unfolded.
It is yet another object of the present invention to provide a folding chair which is""safe and comfortable.
It is yet another object of the present invention to provide a folding chair which is durable, strong, and cost effective.
The above objects and others not specifically recited are realized in a specific illustrative embodiment of a folding chair having a rigid support frame with a curved spline profile, and a seat and rear legs which fold into a closed position and substantially collapse within a volume defined by the support frame, such that the chair maximizes stacking density, and such that folded chairs have the curved spline profile to nest within one another and resist relative movement.
The support frame has first and second rigid side support members, each with an upper back support portion and extending forwardly to form front leg portions. The back support portion and the front leg portions are integrally and rigidly connected to advantageously form a curved spline profile.
A seat is pivotally coupled to the support frame, or to and between the first and second support members. A majority of the seat advantageously collapses to a folded position within a volume defined between the first and second rigid side support members.
Rear legs are pivotally coupled to the support frame, or to the respective first and second support members. A majority of the rear legs advantageously collapse to a folded position within the volume defined by the support frame between the first and second rigid support members.
In the folded position, the chair is relatively thin, and is substantially contained within the support frame and the curved spline profile. Thus, a plurality of chairs advantageously are able to be stacked together with a very high density. In addition, the chairs have a substantially curved spline profile in the folded position. The first and second support members, the seat and the rear legs have a curved spline profile of substantially uniform thickness in the closed folded position. The curved spline profile forms a protrusion and a recess such that a protrusion of a first folding chair may nest with a recess of a second folding chair. Thus, a plurality of chairs advantageously are able to nest together for greater stability.
In accordance with one aspect of the present invention, the support frame and first and second support members preferably are shaped to form a composite curve with an s-shape.
In accordance with another aspect of the present invention, the front leg portions and rear legs are curved. The rear legs advantageously have a radius of curvature smaller than a radius of curvature of the front leg portions. The smaller radius of curvature of the rear legs allows the rear legs to pivot substantially between the front leg portions in the closed folded position. In addition, a bottom portion of the rear legs advantageously extends beyond the volume defined by the rigid support frame when the chair is in a folded position. Thus, the bottom portion of the rear legs advantageously nests with the front leg portions of a second adjacent folding chair to resist lateral relative movement and increase stability of the stacked chairs.
In accordance with another aspect of the present invention, front and rear cross support members couple together the respective front leg portions and the rear legs. At least the front cross support member has left and right channels for substantially receiving a section of a rigid support frame of a second folding chair to increase stability, and to allow the rear legs to further collapse within the volume of the frame.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by the practice of the invention without undue experimentation. The objects and advantages of the invention may be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims.